Allen-Bradley 825-P, User Manual

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Rockwell Automation Publication 825-UM004D-EN-P - November 2012 165
ASCII Serial Communications Chapter 12
You can use the XOFF character to pause in the middle of long transmissions
from the relay. To resume the transmission, use the XON character. To cancel a
transmission in progress, use the
Ctrl+X key commands.
Serial Port Access Levels
Issue commands to the relay via the front serial port, e.g., to view metering values
or change the relay settings. Refer to Table 99 available serial port commands.
Access these commands only from the corresponding access level, as listed
in the table.
Access levels are:
• Access Level 0 (the lowest access level)
• Access Level 1
• Access Level 2 (the highest access level)
Access Level 0
Once serial port communications are established with the relay, the relay displays
the
=
prompt (an equal sign). This is referred to as Access Level 0. The only
command available at Access Level 0 is the ACC command (see Table 99). Type
ACC
at the Access Level 0 prompt and then press Enter. The ACC command
takes the relay to Access Level 1.
Access Level 1
The Access Level 1 commands primarily allow you to view information (such as
settings and metering) but not to change settings. When the relay is in Access
Level 1, the relay sends the prompt:
=>
. Type
2AC
at the prompt and then press
Enter to take the relay to Access Level 2.
Access Level 2
The Access Level 2 commands primarily allow you to change relay settings, reset
data buffers, and control relay outputs. If left in Access Level 2, the serial port
automatically returns to Access Level 1 after a settable inactivity period. All
Access Level 1 commands are also available in Access Level 2. When the relay is in
Table 98 - Serial Port Control Characters
Control Characters Key Commands
XON Ctrl+Q
XOFF Ctrl+S
CAN Ctrl+X